Methods for lateral flow-based biological sample collection

Abstract

A device including a casing first part; a casing second part; a test strip having a sample pad; and a capillary sample collector, wherein the capillary sample collector has an open distal end configured to collect a fluid sample by capillary action and an open proximal end configured to dispense the fluid sample therefrom, wherein, the device is assembled such that the casing first part and the casing second part are joined, wherein a distal end of the casing first part and a distal end of the casing second part are sealed together in a fluid-tight manner, wherein the sample pad is positioned in proximity to the capillary dispensing end, wherein the dispensing end is positioned such that a dispensed fluid sample will be dispensed onto the sample pad, and wherein a dispensing angle between the dispensing and the sample pad of the test strip is less than 10 degrees.

1 .- 27 . (canceled) 
     
     
         28 . A method, comprising:
 providing a capillary sample collector having a distal end and a proximal end, wherein the proximal end of the capillary sample collector has a dispensing opening;   collecting a fluid sample at the distal end of the capillary sample collector, wherein the capillary sample collector is configured to limit an amount of the fluid sample to a predefined volume;   applying a cap to the distal end of the capillary sample so as to form an air-tight seal over the distal end of the capillary sample collector;
 wherein the cap contains a sponge that contains a reagent fluid, and 
 wherein application of the cap to the distal end of the capillary sample collector drives the reagent fluid into the distal end of the capillary sample collector, whereby the reagent fluid drives the fluid sample toward the dispensing opening; and 
   dispensing the fluid sample and at least a portion of the reagent fluid through the dispensing opening and onto a test strip sample pad,   wherein a flow rate of the sample fluid within the test strip sample pad in a direction toward a conjugate pad is greater than a flow rate of the sample fluid within the test strip sample pad in a direction away from the conjugate pad.   
     
     
         29 . The method of  claim 28 , wherein the capillary sample collector comprises a burst valve between the proximal end and the distal end, and wherein the burst valve is configured to limit the amount of the fluid sample. 
     
     
         30 . The method of  claim 28 ,
 wherein the capillary sample collector further comprises:
 a hydrophilic portion positioned at the distal end, and 
 a hydrophobic portion positioned between the hydrophilic portion and the proximal end, and 
   wherein a size of the hydrophilic portion is configured to limit the amount of the fluid sample.   
     
     
         31 . The method of  claim 30 , wherein the capillary sample collector further comprises an air gap positioned between the hydrophilic portion and the hydrophobic portion. 
     
     
         32 . The method of  claim 30 , wherein a volume of the hydrophobic portion is smaller than a volume of the hydrophilic portion, whereby the capillary sample collector is configured to minimize dilution of the fluid sample prior to the fluid sample reaching the test strip sample pad. 
     
     
         33 . The method of  claim 32 , wherein the capillary sample collector is configured such that the dilution of the fluid sample by the reagent fluid is less than 10%. 
     
     
         34 . The method of  claim 28 , wherein the fluid sample is dispensed onto the sample pad at a tilt angle of less than 10°. 
     
     
         35 . The method of  claim 28 , wherein a flow velocity of the fluid sample along the sample pad is between 0.1 mm/s and 1 mm/s. 
     
     
         36 . The method of  claim 28 , wherein the predefined volume is less than 100 microliters. 
     
     
         37 . The method of  claim 28 ,
 wherein an air gap is present between the dispensing opening of the capillary sample collector and the test strip sample pad, and   wherein the dispensing opening and the air gap cooperate to act as a burst valve at the dispensing opening of the capillary sample collector.   
     
     
         38 . The method of  claim 28 , wherein the capillary sample collector is configured to minimize dilution of that a portion of the fluid sample dispensed onto the test strip sample pad. 
     
     
         39 . The method of  claim 38 , wherein the capillary sample collector is configured such that the dilution of the portion of the fluid sample is less than 10%. 
     
     
         40 . The method of  claim 28 , wherein the capillary sample collector is made of glass. 
     
     
         41 . The method of  claim 28 , wherein the capillary sample collector is made of a polymer. 
     
     
         42 . The method of  claim 28 , wherein the capillary sample collector and the test strip sample pad are contained within a casing. 
     
     
         43 . The method of  claim 42 , the fluid sample collected in the capillary sample tube is visible from outside the casing. 
     
     
         44 . The method of  claim 42 , where diagnostic lines of the test strip sample pad are visible from outside the casing. 
     
     
         45 . The method of  claim 28 , wherein the cap is threaded over the distal end of the capillary sample collector to thereby form the air-tight seal. 
     
     
         46 . The method of  claim 45 , wherein the threaded connection between the cap and the distal end of the capillary sample connector is configured to reduce a flow rate of the reagent into the capillary sample collector. 
     
     
         47 . The method of  claim 45 , wherein the cap comprises an O-ring, and wherein the O-ring is configured to facilitate forming the air-tight seal between the cap and the distal end of the capillary sample collector when the cap is threaded over the distal end of the capillary sample collector.